http://science.sciencemag.org/content/359/6371/69
). The main episode of massive star formation began about 8 million years (My) ago, and the star-formation rate seems to have declined in the last 1 My. The IMF is densely sampled up to 200
and contains 32 ± 12% more stars above 30
than predicted by a standard Salpeter IMF. In the mass range of 15 to 200
, the IMF power-law exponent is
, shallower than the Salpeter value of 2.35.